"Do you want praise for noticing the obvious?" he asked, mildly. He isn't being insulting, and isn't angry even here and now. It's simply a continuation of their discussions - and the physical discussion happening in swordplay.

However, it's a controlled defense and when he's pushed as far as he intends to go - or indeed can go - by Malgus' offense, he abruptly and smoothly switches to an Ataru sequence, using it to change his geography - to literally move himself to a better position on the ground - and then slips right back to Soresu.